Kinetics and spectroscopy of atmospherically important molecules and their degradation products

• Main Author: Hansen, Jaron Conly
• Other Authors: Francisco, Joseph S.
• Format: Text
• Language: English
• Published: Purdue University 2002
• Subjects: Analytical chemistry|Environmental science; Arctic
• Online Access: https://docs.lib.purdue.edu/dissertations/AAI3099785

The present research will explore the impact that both natural and anthropogenic activity has on both the upper and lower atmosphere. The impact on the upper atmosphere, specifically the ozone layer, from the introduction of chlorine and bromine containing compounds is a well characterized event that leads to the removal of ozone, and production of BrO radicals and O2. Few mechanisms have been proposed for converting the BrO radical into ozone scavenging Br atoms. This work proposes two mechanisms and their accompanying kinetics that would convert BrO radicals into photolytically labile BrOH. The proposed mechanism and accompanying kinetics also help to explain the correlation that is observed between ambient ozone and formaldehyde concentrations in the Arctic. Due to the destructive nature of bromine to the ozone layer, the sources of bromine atoms in the stratosphere has received considerable experimental and theoretical attention. Missing from previous studies is an evaluation of the degradation mechanism of CHBr3 and the subsequent products from the decay of CHBr3 under atmospheric conditions. The kinetics for the decay of CHBr3 under atmospheric conditions as well as the spectroscopy and photochemistry of the reaction products will be reported in this work. In addition, the kinetics and spectroscopy of the degradation products of methyl formate will be presented in this work. Recommendations for further research as it pertains to the impact of hydrocarbon release in the troposphere as well as their impact on the stratosphere will be presented in the final sections of this thesis.